Iodide for the management of Graves' disease in pregnancy.

There is considerable variation among European, American, and Japanese guidelines regarding the management of Graves’ disease (GD) in early pregnancy. In contrast to European and the American Thyroid Association’s recommendations, the Japanese Thyroid Association includes potassium iodide (KI) as an alternative treatment option, reflecting long-standing clinical experience in iodine-sufficient populations. This review summarizes the historical background, pharmacologic mechanisms, and clinical evidence related to KI therapy in pregnant women with GD, with particular emphasis on data derived from Japanese clinical practice. The potential benefits, limitations, and safety concerns in regard to treatment with KI, including its rapid antithyroid effect and the risk of treatment escape, are discussed. The review also highlights areas of uncertainty and the need for careful patient selection and monitoring when treatment with KI is considered.